Rezko is the kind of neighbor you want—the absent kind—and he might be absent for a long time—in the federal pen. That move upriver might keep Obama from his own residential upgrade to that big white house he's got his eye on in Washington.

OK, I'll stop. When you read the Chicago columnists having fun with the relationship between Obama and Rezko, the wiseacre rubs off on you. Here's the story, without the mustard: Barack Obama has a little real-estate scandal that raises questions about his judgment.

The Chicago Tribune broke the story back in November. It begins in 2004 with Obama's $1.9 million book advance for The Audacity of Hope. In June 2005, Obama used the money to purchase a $1.65 million Georgian revival home on Chicago's South Side—$300,000 less than the asking price. On the very same day, Rezko, a Democratic Party fund-raiser and developer, bought the adjacent empty lot at the asking price from the same owner (the house and the lot were previously owned by the same person). Rezko, who had raised money for Obama and known him since the senator attended Harvard Law School, did not develop the empty lot. In January 2006, he sold a 1,500-square-foot slice of it to Obama for $104,000, a fair sum in that market.

Here's the question: Did Rezko orchestrate his same-day purchase of the lot at full price so that the seller would give Obama a break on the price of the adjacent house? Was Obama in on the deal? And did Rezko never intend to develop the lot, giving Obama a nice roomy side yard, a favor which he'd call in later?

Obama says he did talk to Rezko before the purchase, but only because a person who had renovated it for a previous owner had once worked with Rezko, who owns other properties in the South Side. He didn't arrange the joint purchase with him. He bought the house at such a good price, Obama has told the papers, because it was being unloaded in a "fire sale."

There's no evidence that the senator is fibbing or that the indicted fund-raiser asked anything in return for his neighborly behavior (though that might have been just a matter of time). Obama hasn't tried to change his story, even though Rezko is now talking to investigators.

What about Obama's judgment? Chicago politicians with national aspirations have to think a little harder about appearances than their colleagues from other cities that don't have reputations for corruption. Shouldn't Obama have known not to get anywhere near a sketchy character like Rezko?

When Obama bought his house, Rezko was not as radioactive as he is today. Newspaper accounts contained allegations about his business practices, but he was regarded as a typical power broker who cannily cultivates politicians. But by the time that Obama bought the strip of land, Rezko was glowing. The papers were reporting that he was under investigation by federal prosecutors. In October, he was charged in a 24-count indictment with trying to obtain kickbacks from companies seeking state business.

Obama presents himself as a squeaky-clean politician, so the dubious association with Rezko has caused him more trouble that it would, say, anyone else in the history of Chicago or Illinois politics. To defuse the issue, the junior senator has done a good John McCain imitation: swamping critics with apologies, admissions, and candor. "This is the first time this has happened and I don't like the feeling," Obama said at a press conference in November. "It's frustrating to me, and I'm kicking myself about it." He told the Associated Press: "Purchasing a piece of property from somebody who has been a supporter of yours I think is a bad idea. It's an example of where every once in a while you're going to make a mistake and hopefully you learn from it." He told the Chicago Sun-Times that he made a mistake and, "I regret it. ... One of the things you purchase in public life is that there are going to be a different set of standards, I'm going to make sure from this point that I don't even come close to the line."

As the scandal stands, this is not Obama's Whitewater, the Arkansas land deal that bedeviled Bill and Hillary Clinton during the early part of President Clinton's first term. It doesn't help an inexperienced national politician to have to admit a stupid rookie mistake before the cameras, but there's nothing here so far that seems politically life threatening. Of course, if Rezko tells a different story to investigators or Obama's statements turn out to be untrue, that's it for him—you can't run for president on your keen judgment and then show a lack of it by lying and covering up.

If Obama decides to run for president and fails, it will be because he'll show in other ways that he lacks experience, or he can't handle the rigors of a campaign, or because he turns out to speak only in pleasing generalities. The Rezko business is also not likely to hurt him, because his principal rival will probably be Hillary Clinton, and she's not going to bring up the topic of questionable land deals.